A number of different techniques have been devised and used to provide for reduction of a displaced fracture and for the maintenance of the same during fracture healing. For the most part, the devices used to set the fracture of the distal radius in the forearm have been unsatisfactory for one or more reasons. In particular, external fixators (hereinafter referred to as splints) which have been known and used in the past have not been properly designed to provide selective and continuously adjustable degrees of distraction across the fracture site by means which allows for independent adjustment for both appositional and rotational alignment of the same fracture so as to provide the capability of easily returning the distal and proximal fragments to there proper location and to hold them in such locations until the fracture has healed.
Another drawback with the use of conventional splints used to treat a fracture is the fact that such splints are comprised of metallic parts, such as rods, screws and pin-holding members which span the fracture site. Such metallic parts are opaque to x-rays and do not permit viewing of all aspects of a fracture site in x-ray photographs.
The third major drawback with the use of conventional splints for treating a fracture is in the design deficiencies which prevent the selective displacement of the hand and thereby the wrist and distal fragment of the radius in a radial and ulnar direction while isolating this aspect of the fracture reduction from the other three aspects of the fracture reduction, namely, apposition in a dorsal-palmar direction, rotational alignment, and length or degree of distraction. Thus, with conventional splints, it is not possible to manipulate the fracture reduction in a radial and ulnar direction without losing the beneficial adjustments provided by the other three aspects of fracture reduction.
A further drawback, associated with conventional splints is that they do not allow for selective extension and flexion of the wrist joint itself. Such extension and flexion can frequently facilitate fracture reduction and/or minimize the risks of extensor tendon "overpull" through wrist extension. Specifically, wrist extension relaxes the tension on the finger extensor tendons and thereby minimizes the risk of producing a stiff hand by allowing more flexion of the metacorpophalangeal joints of the fingers.
A prior disclosure relating to a Colles' type fracture splint is U.S. patent application Ser. No. 321,150, filed Nov. 13, 1981 by John M. Agee. This disclosure describes two embodiments of a fracture splint, one of which provides distraction of the distal and proximal bone fragments relative to a fracture site and the other being designed to project an axis from its two major moveable parts that becomes coincident with the rotational axis about which most Colles' type fractures typically rotate. Both of these embodiments have metallic parts which render it difficult to provide x-ray photographs of the fracture site with the splint in place. Moreover, neither embodiment allows for selective adjustment of appositional alignment as appreciated from the anterior-posterior x-ray view, i.e., adjustments of the radioulnar alignment of the fracture. Further, neither embodiment allows for wrist flexion and extension.
Because of the foregoing drawbacks, improvements in a Colles' type splint are needed to provide for proper treatment of Colles' type fractures.